Description: This project will have two sub-projects. In the first, they will the examine role of market forces - managed care penetration - in the appropriate use of angiography and drug treatment for Medicare patients with AMI. They will also examine managed care penetration and mortality and reinfarction. This project will use data from Cooperative Cardiovascular Project, Baker?s market designations, a modified version of the RAND appropriateness instrument, and concordance with a guideline for drug therapy. They will employ a two step hierarchical model, with the first being a patient level and the second a market level. By using a more extensive set of covariates, they will have better case-mix adjustment than other studies have had. In the second project, they will look at quality and outcomes of care for shock, acute GI bleed, pulmonary embolus, and AMI as competition changed in New Jersey following the 1992 of New Jersey's rate setting approach. New York will act as a control state. HCUP data will be used. They will examine cardiac catheterization and cardiac revascularization for patients with AMI, endoscopy for GI bleeds, pulmonary angiograms for patients with embolisms. In each case the object of study is the rate or likelihood, not its appropriateness. Outcomes will include mortality. The advantages of these four conditions is that they are exclusively treated in an inpatient setting - if the patient makes it that far. Thus, there should be no selection issues caused by lower likelihood of hospitalization or switching care to outpatient settings under more stringent health care plans. The second project is basically a before and after comparisons with a contemporaneous control group to capture secular trends.